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bobbybrown
19-06-2008, 03:10 PM
Got a little problem here folks. Its got me stumped to say the least.

Just done the head gasket on a peugeot 106 for a customer, all went well.
I usually put the coolant temperature sensor back on to the head before I fit the head to the car, but guess what? I didn't this time!

Screw it in by hand a couple of turns, get the spanner on it, 2 more turns and crack.
Broken.
Now, its stuck in the head, I ain't taking the head off again so I need to find a way to get it out with the head in place.
Inside the head, there is the end of the sensor that heats up, and sticking out of the head is the small metal tab thats usually inside the sensor.
There are no threads showing outside the head.
This is what the sensor looks like, it has broken off just after the nut at the top, all I have left is the sensor plug, the nut and about 3 threads, the rest is inside the head!!
http://snuo.win.mofcom.gov.cn/www/8/snuo/img/20071127104716.jpg

Any ideas?
I need to get this sorted tomorrow :cry:

Big Birds Car
19-06-2008, 03:37 PM
Best idea from me is a large easi out. I have tried many times over the years to use them effectively without much luck but I did manage to use them last year to remove broken exhaust studs in a 205 from underneath, I was able to get a drill in the centre of the studs and then used the correct easi out (come to think of it, this is probably the only time it worked, usually snapped the easi out in the hole as well).

Anyway if you are able to get a little heat to the broken eliment before hand and then use the correct size easi out you may have a chance.

Alternatively, if you are able to gain plenty of access around the offending item you could use a tiny punch and a hammer and try "unscrewing" it that way. If you do this put a bit of cloth or tissue in the hole first incase any swarf gets chipped off and goes in the head (don't want any bits floating around in the water system).

Last ditch attempt would be a flat screwdriver tapped in as an interference fit and try to unscrew it but by now all else has failed and this isn't the best way forward, as you will probably knacker the threads up for the new unit going back in.

Best I can come up with I'm affraid. Good Luck.

bobbybrown
19-06-2008, 05:09 PM
One thing I lack at the moment is easi outs.
They got stolen along with my tool box not so long ago.

I'm thinking its going to be a pain, it can't be that tight, but it did tighten up right before it snapped, kind of a sudden tightness and then crack.

I'll have a look at it tomorrow and see what I can do, if anything.

Cheers for that Paul.

Alzax3
19-06-2008, 08:57 PM
It all depends whether the thread is tapered, in which case it could be very tight. If it isn't then it depends whether the chamfer above or below the thread is what has caused the 'sieze up', if it's the one above the thread, and that's where it broke, there won't be a lot of tension on the remaining part and it should spin out quite easily (shear the head of a bolt by over tightening when it's touched the surface and the threaded part of the bolt can sometimes be run back out with a finger tip!) Screw driver blade or tapping round with a punch as BBC suggests were the first things that came to mind too :D

bobbybrown
19-06-2008, 11:47 PM
I'll give it a go tomorrow and see what happens.

Hopefully I can get it out :rofl:

suicidesam
20-06-2008, 08:15 AM
would this do the job ? the price is right anyway ! :clapping:

http://www.screwfix.com/prods/18643/Dri ... ctor%20Set (http://www.screwfix.com/prods/18643/Drill-Bits/Specialist-Drill-Bits/Screw-Extractor-Set?cm_mmc=GoogleBase-_-Datafeed-_-Drill%20Bits-_-Screw%20Extractor%20Set)

Alzax3
20-06-2008, 08:33 AM
It's the right sort of thing, though I've always found that particular design more prone either to shear off oin use or work like a reverse drill and cut away the inside of the offending article. At least if you don't have to be quite as careful with getting fragments into the water jacket as you would into an oil way, but the water pump won't like any big indiscretions........

bobbybrown
20-06-2008, 08:56 AM
Only problem with that is, the sensor thats left inside the head is hollow.
Just been thinking about it and its hollow, so its going to be more of a pain to get out.

Alzax3
20-06-2008, 09:05 AM
No that makes life easier, because if it wasn't hollow, you'd have to be drilling a hole in it......it also means that the punch and hammer method (or the screw driver jamming for that matter) is more likely to work. Good luck Dan!

bobbybrown
20-06-2008, 10:58 AM
I never thought of that.
I'll try screwdriver and hammer method first, tapping it to see if I can undo it, and if not I'll move on to more destructive ways :twisted:

bobbybrown
21-06-2008, 02:28 PM
Sorted!
Nice and easy in the end!

Steve, when you looked yesterday and tried with the screwdriver, I repeated that today, but using a lump hammer to knock it in, instead of the mole grips, and it bought it straight out!

All well and good now, looks like the peugeot can be picked up and the next job dropped off!

Thanks for all your help to everyone who replied here.

Alzax3
21-06-2008, 09:39 PM
Excellent! :cheers: :cheers:

Big Birds Car
21-06-2008, 10:41 PM
Good old trusty screwdriver wins the day again, well done.